Oracle Blog

A. Sundararajan's Weblog

Sunday Dec 13, 2009

Sometimes you may want to quickly generate graphs programmatically and view/analyze those. Examples include, inheritance/type relation diagrams of an object oriented program, function call graphs and any other domain specific graphs (reporting chain of your organization chart for example). I find GXL very useful for this. GXL stands for Graph eXchange Language. It is a simple XML format to specify graphs. A simple graph stating that "JavaFX" language is related to "Java" language is as follows:

Now that we have written a simple graph with two nodes and a single edge between them, we may want to view it. There are number of tools/libraries to view GXL documents -- I've used Graphviz. Graphviz displays it's own native format called ".dot". Graphviz comes with a set of command line tools. One such tool is "gxl2dot", which as you'd have guessed, can be used to convert a .gxl file to a .dot file.

gxl2dot Test.gxl > Test.dot

Once converted the .dot file can be opened in Graphviz GUI and we can export it to .pdf/.jpg/.png and so on. This way you can email the graphs to others and/or publish in your blogs/webpages easily.